Quantum technologies are changing our lives. Research into the smallest energy particles (known as quanta) puts us tantalisingly close to opportunities that were long considered to be out of reach. New concepts are providing solutions to the key challenges of our time: for complex interactions relating to resource efficiency as part of the energy revolution, improved traffic flows thanks to real-time data, or eavesdropper-proof communications via quantum encoding. 

Quantum physics appears to turn the laws of nature on their head. Although it is one of the fundamental pillars of modern physics, it can often seem mystifying: take entangled particles that have a form of long-distance relationship, the difficulty of measuring them, or the fact that they can be in several states at once. Nevertheless, quantum physics is already playing a key role in everyday life, from atomic clocks to lasers to magnetic resonance imaging (MRI) – all inventions that would have been impossible without it.

Working with photons has its challenges. The common sources used to produce these tiny particles are still relatively imprecise. However, as their targeted manipulation is one of the most important key elements of quantum technologies, (further) fundamental research in the field is vital. Physicists at Paderborn University have been continually working to develop innovative concepts for individual photons with tailored properties. This enables them to manipulate the shape of photons, their energy content and the information they transmit. Specifically, the technology is used in areas such as quantum cryptography.

Paderborn’s researchers are also working to develop scalable methods for quantum system control.. These enable the sources of individual photons to be precisely controlled using ultrafast electronics. However, these are also particularly interesting to explore as they are a prerequisite for something being worked on by big players in the technology and IT sectors: they form the basis for ‘quantum computers’. These are special computers that differ from traditional computers in that instead of using bits, they work on the basis of quantum mechanical states.

Quantum computers are one of the key future technologies of the 21st century, with their potential exceeding even that of the best supercomputers. As high-performance tools, they can solve even the most complex of computational problems – tasks that push traditional hardware and software to their limits and beyond.

In the future, Paderborn will play host to every step in this process, from fundamental research into new quantum algorithms to large, complex quantum systems to real photonic quantum networks for relevant computing applications. Together with partners from science and industry (in Germany and worldwide), the researchers are working on projects such as chips for photonic quantum computers. Areas of potential application include the chemical industry, drug discovery and materials science.